1. Field of the Invention
The present invention is concerned with novel compounds which are N-[(2-amino-5-halo-6-(substituted)-3-pyrazinyl)methylene]amines, but will be referred to hereafter as novel pyrazines.
The present invention is also concerned with antimicrobial compositions containing these novel compounds as active ingredients, as well as with a method of inhibiting the growth of bacteria and fungi by contacting said bacteria and fungi with the novel compounds of the present invention. These novel compounds have a number of important industrial and agricultural applications.
As used herein, the terms "antimicrobial" "bactericidal", and "fungicidal" describe the killing of, as well as the inhibition of or control of the growth of bacteria and fungi. A number of important industries can experience serious adverse effects from the activity of such bacteria and fungi on the raw materials which they employ, on various aspects of their manufacturing activities, or on the finished products which they produce. Such industries include the paint, wood, textile, cosmetic, leather, tobacco, fur, rope, paper, pulp, plastics, fuel, oil, rubber, and machine industries. Important applications of the novel antimicrobial compounds of the present invention include: inhibiting the growth of bacteria in aqueous paints, adhesives, latex emulsions, and joint cements; preserving wood; preserving cutting oils; controlling slime-producing bacteria and fungi in pulp and paper mills and cooling towers; as a spray or dip treatment for textiles and leather to prevent mold growth; as an additive to polyvinylchloride and other plastics to prevent growth thereon and degradation thereof by bacteria and fungi; as a component of anti-fouling paints to prevent adherence of fouling organisms; protecting paint films, especially exterior paints, from attack by fungi which occurs during weathering of the paint film; protecting processing equipment from slime deposits during manufacture of cane and beet sugar; preventing microorganism buildup and deposits in air washer or scrubber systems and in industrial fresh water supply systems; controlling microorganism contamination and deposits in oil field drilling fluids and muds, and in secondary petroleum recovery processes; preventing bacterial and fungal growth in paper coating processes which might adversely affect the quality of the paper coating; controlling bacterial and fungal growth and deposits during the manufacture of various specialty boards, e.g., cardboard and particle board; preventing sap stain discoloration on freshly cut wood of various kinds; controlling bacterial and fungal growth in clay and pigment slurries of various types which are manufactured for later use in paper coating and paint manufacturing for example, and which are susceptible to degradation by microorganisms during storage and transport; and as a hard surface disinfectant to prevent growth of bacteria and fungi on walls, floors, etc. The control of bacteria and fungi in pulp and paper mill water systems which contain aqueous dispersions of papermaking fibers is especially important. The uncontrolled buildup of slime produced by the accumulation of bacteria and fungi causes offgrade production, decreased production due to breaks and greater cleanup frequency, increased raw material usage, and increased maintenance costs. The problem of slime deposits has been aggravated by the widespread use of closed white water systems in the paper industry.
Another important area where control of bacterial and fungal growth is vital is in clay and pigment slurries. These slurries are of various clays, e.g. kaolin, and pigments, e.g. calcium carbonate and titanium dioxide, and are manufactured usually at a location separate from the end use application, in for example, paper coating and paint manufacturing, and are then stored and held for later transport to the end use location. Because of the high quality standards for the paper and paint final products in which the slurry is used, it is essential that the clay or pigment slurry have a very low microorganism count or content so that it is usable in the paper coating or paint manufacturing.
The novel antimicrobial compounds of the present invention may also be utilized for agricultural and animal health applications, for example in preventing or minimizing the growth of harmful bacterial and/or fungi on plants, trees, fruit, seeds, or soil. At the same time there is obtained by their use a pronounced growth-stimulating action producing not only an abundant root system but also a luxuriant growth above ground, this being accompanied by a substantial increase in the yield of the crop per acre as compared not only with untreated plants and soils, but also with other, widely used foliar and soil fungicides. The novel antimicrobial compounds are especially useful in treating seed to prevent microorganism, particularly fungal attack. The novel antimicrobial compounds are also useful in protecting animal dip compositions against the buildup of microorganisms, and for this purpose may be combined with a veterinary animal dip parasiticide and an acceptable carrier.
The novel antimicrobial compounds of the present invention have been found especially useful in controlling the harmful effects of microorganisms in water or aqueous media. Systems which utilize circulating water or aqueous media become infected with microorganisms and experience substantial impairment of thier efficiency when deposits of the microorganisms build up in the system. The deposits, called slimes, coat the walls of tanks and other vessels, and any machinery or processing equipment which is employed, and create blockages in pipes and valves. The slimes also create discolorations and other imperfections in any products being produced, forcing costly shutdowns. Control of microorganisms in aqueous media is particularly important where there are dispersed particles or fines in the aqueous media, e.g., dispersed cellulosic fibers and dispersed fillers and pigments in papermaking, and dispersed pigments in paint manufacture.
2. Brief Description of the Prior Art
Cragoe and Jones, U.S Pat. Nos. 3,274,192; 3,299,063; 3,341,540; and 3,487,082 all disclose various pyrazine compounds useful as diuretics. However, the novel pyrazines of the present invention are not suggested, nor is their use as antimicrobial agents.
Donald, U.S. Pat. No. 4,054,655 describes the use of aminodicyanopyrazines for controlling plant diseases caused by fungi. However, the novel pyrazines of the present invention are not suggested.
Grier et al., U.S. Pat. Nos. 4,145,426; 3,626,060; and 4,119,779 all describe various antibacterial and antifungal compounds for agricultural and industrial use. However, none of these compounds are pyrazines, and the novel pyrazines of the present invention are not suggested.
Kohn and Singer, U.S. Pat. Nos. 3,854,000 and 3,763,176 describe the use of certain thiadiazolin-4-ones as antimicrobial agents. However, the novel pyrazines of the present invention are not suggested.
Albert and Clark, J.C.S., 1666-1673 (1964), describe various pyrazines. However, no use for these pyrazines is suggested, and the novel pyrazines of the present invention are not suggested.
Kyowa published Japanese application No. 5164-606 describes 2,3-dicyanopyrazine compounds used as antimicrobial agents. However, there is no suggestion of the novel pyrazine compounds of the present invention.